Active matrix organic light emitting diode (AMOLED) display is a display technique applicable to a TV set and a mobile device, and has wide application prospect in power-sensitive portable electronic devices due to its characteristics of low power consumption, low cost and large size.
At present, in the AMOLED display field, in particular the large-size substrate design, a backplane thin film transistor (TFT) has non-uniformity and stability problems in the manufacturing process, which will not only cause threshold voltage offset due to non-uniformity of a driving OLED current, but also have the problem of TFT stability decrease after a long time of turning on bias voltage.
In the prior art, there are many AMOLED compensation circuit designs performed by only considering the problem of threshold voltage offset but neglecting the problem that load on a signal line will be increasing with the trend of the large-size AMOLED, thereby resulting in occurrence of voltage attenuation on the signal line, so as to influence the uniformity of current in the display area.